My favorite component is my Wavebourn Pyramid VII, Prototype 1, built to my specs and as far as I know, the only one in existence. I originally bought the Pyramid V, also a prototype that was damaged during shipping (as seen below). I always wanted to try a tube amp but I've got some terribly inefficient Magnepans and the tube power needed to drive them was just too cost prohibitive. After searching for months I rolled the dice on the Wavebourn and it's been the best stereo purchase I ever made. The designer, a Russian dude from Cali, was basically going to lose his home unless he raised some quick cash...so I got this amp for less than the cost of the power supplies. The V was originally designed to be used in a PA system and as a guitar amp. After seeing it on Audiogon I researched Anatoily, the designer, and what little I could find out about him he seemed very well respected among his peers. When the V showed up the power supplies were literally ripped from the chassis so, to make a long story short, it took six months but he tweaked the circuitry and I ended up with the Pyramid VII. I've had Acurus, Rotel and some other lesser SS amps in this system and the Wavebourn is by far the best sounding. Very, as they say, musical...and not fatiguing at all. The truth is that I bought this amp because I liked the way it looked. I love it for how it sounds and I'll never part with it because of the history I have with it and the uniqueness/cool factor. At 80W X 2 it drives the Maggies but not quite as loudly as I like when cranking NIN, Rob Zombie, etc. For classical, jazz and blues though...

However I have a feeling that none participating in this thread (other than maybe Thorsten) is actually interested in my findings.

I'm interested if there's enough details about what you hear and what the experimental set-up was. Mere 'better' or 'preferred' or 'changed' is boring, but what music you played and a description of the changes in the perceived sound of that music would be all good stuff.

__________________"Having people devoted to attacking you – even in unfair, invalid or personal ways – is actually valuable for keeping one honest and self-reflective." - Glenn Greenwald

I tried to e-mail you, but it looks like something is broken here: instead of e-mail page I am getting support.diyaudio.com page with unrelated information. Send me e-mail and I introduce you to each other.

As usual purpose objectivism at it's bets barking up the wrong tree in the wrong woods to boot. Worse, being what I would consider not just disrespectful, but in subsequent posts outright insulting to some of the contributors here...

There are reasons why power cables make a difference, in mains powered systems using multiple interconnected devices. These are good, scientific reasons, that can be measured and easily understood. And powersupply design as such has little or nothing to do with it (Powersupply Transformer design does, however only in an indirect sense.

The mechanisms have been covered in thishere venue and other with quite some repetition, so I shall not add to this repetitive pattern (no need to go over old battlegrounds), other than noting that it has much to do with common mode impedances, circulating chassis currents and ground noise...

I'm with you, Joshua. What you hear is what you have. Don't try to 'prove' anything to anyone else. It's unfortunately pointless. I personally do my best with what I have, help others when they ask me, and am satisfied when third parties, like audio reviews, like my work, and say so in print. That to me, is 'success'. Just because I got 'Phonostage of the year' this year in TAS, just wait until next year, when my 'big guns' become operational.

However I'm curious why Thorsten Loesch bothered to put a special AMR fuse in the CDP I purchased recently.

I really also want to know why I bothered to put special fuses there...

I cannot explain why. It goes against anything I know how electricity and electrics behave. I could possible see the point in a big poweramp where varying load may modulate the Fuse impedance which would modulate the supply voltages with signal and could cause audible effects.

But in a CD-Player? With "Class A" Shunt regulators in all critical positions and Class A Tube Analogue circuitry there can be no change in current with signal. And the small differences in loop impedance from using a straight wire inside the fuse instead of a spiral plus the use of gold plated brass end-caps cannot be held responsible for any appreciable differences, as least not according to existing electronic theory.

Maybe it as a just a pigment of my Imagination? But I's don't have no imagination! And what about these statistics from the listening tests?

In short, I am extremely puzzeled as to why I put them there. If I ever find out, I might still have a shot at that Nobel Prize.

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Originally Posted by Joshua_G

Was the fuse chosen after certain measurements? Or may be after listening evaluations? Is that special fuse only for show? I doubt it, since most customers don't bother to take out the fuse and look at it.

Ahh, I see I misunderstood your question in part (okay, in part deliberately for dramatic and comic effect).

Well, a long time ago I had just broken up with a GF and was not up for a new relationship or even casual hanging out (As Carly Simon once so famously sang: "Don't mind if I fall apart, there's more room in a broken heart").

So I buried myself in tedious, mind numbing stuff, such as putting RCA Plugs onto all kinds of cables I could get my hands on and listening to them (single-blind) and even listening to the different Fuses one could buy in the various shops. Now Britain is Fuse Central, with one even in each mains plug and in those days we had a profusion of fuses, some remaining small "stuff" shops even sold decades old UK made fuses, not just cheap PRC made stuff.

I found out many cute and interesting things about cables and fuses in these month that still puzzle me no end, until I found a cute and interesting girl to puzzle me instead (I prefer to be teased, puzzled and otherwise occupied by cute members of the opposite sex very much to being teased, puzzled and otherwise occupied by physics/electronics/audio conundrums).

Later at AMR I remembered some of this stuff and we did some new listening tests confirming my old results so we tinkered some more and since use these fuses all over. They have even proven a minor sales hit (there is not much money to be made on fuses, even high end ones at high end prices).

And we had to start making all sorts of specials, including UK Plug fuses (special size) and I believe there is now a fuse specially designed for the tweeter protection in Magnepan Speakers with "blow" characteristics to match the originals and people are just about raving about these.

I find all this fuse hubbub and kerfuffle about fuses distracting and feel a bit like the sorcerers apprentice. Maybe next time I just keep me big gob shut, big old gobshite I am...

I did try different approach that renders such tests meaningless: filtering and stabilizing of voltages and currents. Also, transformer balanced inputs help a lot... According to my experience resources are always limited, contradict each other, and have to be applied where they give better results.

Wavebourn, it would be correct to understand, that you always try to diminish the power cord effects, but I doubt that you pretend to say that you always manage to suppress these effects completely.
Every designer in the world would like to succeed in this, but this task can hardly be solved for class AB power amp, offering high peak currents to speakers, with power supply located in the same case with the rest of schematics.
In some less practical cases, like external PS, constant current consumption from PS independent on signal yes/no, one can really succeed in getting no any effect from power cord. Just good screening and multistage filtering with good caps needed, at all reasonable points.

Wavebourn, it would be correct to understand, that you always try to diminish the power cord effects, but I doubt that you pretend to say that you always manage to suppress these effects completely.

Vladimir;
there is nothing absolute in this world where everything is entangled. I can not suppress anything absolutely. But I can guarantee that when an amp is properly designed there is no difference between properly selected computer grade power cord and something you can buy for crazy money.

Quote:

Every designer in the world would like to succeed in this, but this task can hardly be solved for class AB power amp, offering high peak currents to speakers, with power supply located in the same case with the rest of schematics.

I did not ask every designer in the world if they are getting such good result as I do, so I can not speak for them. I can speak for myself only: when the system is optimally designed it sounds. But if it is not, no power cords can save it from being a garbage.

Quote:

In some less practical cases, like external PS, constant current consumption from PS independent on signal yes/no, one can really succeed in getting no any effect from power cord. Just good screening and multistage filtering with good caps needed, at all reasonable points.

Back in USSR some computers were built in bunkers, in Faraday shields, and powered through electro-mechanical converters. We can do the same and listen music in bunkers, but it is not my way...

Edit: most challenging thing in this regard is not a power amp. And not a phono preamp. It is a recording console that has multiple ins and outs, different signal levels, and each in/out has ground, each cable has a shield, and they can be interconnected by multiple ways. And you know, designers of consoles and their users don't cry aloud about power cords. Well, what audio engineers are often crying about, they are getting nasty garbage when connect their consoles to computers with DAWs. But again, this problem is not so big when you know how to deal with it.